The lead character of Sebastian Lelio’s film “A Fantastic Woman “ is named Marina. She is a nightclub singer and a waitress. She has a boyfriend, Orlando, who is much older than her, but that matters little. They are clearly smitten with one another and in that post-honeymoon phase of the relationship where things still are passionate, but also calm and comforting. They are planning a trip together. She is moving in. Life is moving along nicely it seems.

Marina also is a transgender woman, portrayed by a transgender actress, Daniela Vega. If you have heard of “A Fantastic Woman,” which recently picked up a best foreign language film nomination for Chile, you likely have heard this fact. It might even be the only thing you know about it.

What is astonishing about the actual experience of watching “A Fantastic Woman” is how small of “a thing” it really is, and in that way perhaps one of the truest expressions of modern transgender life that we have ever seen in a fictional film. Marina is just Marina. She has a delicate beauty, and a cool choppy Alexa Chung-like haircut and style. On stage, she is performs with a sultry confidence. Off stage, she is quieter and almost reserved, but very present, especially around Orlando (Francisco Reyes).

But one night, Orlando dies suddenly and Marina’s tranquility is thrown into a tailspin — not just from the death of her love, but from all the unnecessary and often ridiculous complications, some bureaucratic, some purely emotional, that emerge and seem to stem from the fact that she is transgender.

At the hospital where Orlando dies, the fact that her legal name still is her birth name and not Marina becomes an issue with a cop (who an uncomfortable doctor calls when she leaves the scene after he is pronounced dead). A social worker, too, becomes obsessed with checking on Marina, which she continues to explain is just a matter of procedure and to ensure that she was not abused or a sex worker, but which feels nothing but invasive and inappropriate from Marina’s perspective. Orlando’s family, too, is unconscionably cruel to her — save for his brother, Gabo (Luis Gnecco), who seems to be the only person in the film empathetic to the fact that Marina is just a human who has lost a loved one.

Every day is filled with the ever-present threat that someone is going to be uncomfortable with her. Marina is gracious and accommodating almost to a fault, both to the insidiously subtle kinds of judgment and the more outward violence and hatred. Orlando’s ex-wife tells her in no uncertain terms that she is not welcome at the funeral or wake. His grief stricken son is disgusted by her and makes no attempt to hide. And all Marina wants to do is grieve in her own way.

Lelio’s film occasionally delves into some magical realism as Marina struggles to maintain her composure amid such callous inhumanity from so many people, which is a beautiful if jarring disruption in a film that’s otherwise so committed to reality.

It is Vega’s extraordinary performance, full of grace and depth, that keeps “A Fantastic Woman” in check from becoming something either too campy or too sanctimonious. It’s one that has the power to make an audience really understand and internalize why it is an act of bravery to simply live life as herself, and perhaps even change some minds in the process.

“A Fantastic Woman,” a Sony Pictures Classics release, is rated R by the Motion Picture Association of America for “language, sexual content, nudity and a disturbing assault.” Running time: 104 minutes. Three stars out of four.